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Abstract Flexible metal–organic Frameworks (MOFs) are an interesting class of materials due to their diverse properties. One representative of this class is the layered‐pillar MOF DUT‐8(Ni). This MOF consists of Ni2paddle wheels interconnected by naphthalene dicarboxylate linkers and dabco pillars (Ni2(ndc)2(dabco), ndc = 2,6‐naphthalene–dicarboxylate, dabco = 1,4‐diazabicyclo‐[2.2.2]‐octane). DUT‐8(Ni) undergoes a volume change of over 140% upon adsorption of guest molecules. Herein, a ligand field molecular mechanics (LFMM) study of the CO2‐induced flexibility of DUT‐8(Ni) is presented. LFMM is able to reproduce experimental and DFT structural features as well as properties that require large simulation cells. It is shown that the transformation energy from a closed to open state of the MOF is overcompensated fivefold by the host–guest interactions. Structural characteristics of the MOF explain the shape of the energy profile at different loading states and provide useful insights to the interpretation of previous experimental results.
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Inter‐Network Charge‐Transfer Excited State Formation Within a Two‐fold Catenated Metal–Organic Framework
Abstract Charge‐transfer excited state (CTES) defines the ability to split photon energy into work producing redox equivalents suitable for photocatalysis. Here, we report inter‐net CTES formation within a two‐fold catenated crystalline metal–organic framework (MOF), constructed with two linkers, N,N′‐di(4‐pyridyl)‐1,4,5,8‐naphthalenetetracarboxydiimide (DPNDI) and 2,6‐dicarboxynaphthalene (NDC). The structural flexibility puts two complementary linkers from two nets in a proximal position to interact strongly. Supported by the electrochemical and steady‐state electronic spectroscopic data, this ground‐state interaction facilitates forming CTES that can be populated by direct excitation. We map the dynamics of the CTES which persists over a few nanoseconds and highlight the utilities of such relatively long‐lived CTES as enhanced conductivity of the MOF under light over that measured in dark and as a proof‐of‐the‐principle test, photo‐reduction of methyl viologen under white light.
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- Award ID(s):
- 1944903
- PAR ID:
- 10380299
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 29
- Issue:
- 2
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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